Device for correcting finely and when working the amplitude of the advance movement of a band of cardboard in a shaping machine



Novhls, 1941.

H. BOBST DEVICE FOR CORRECTING FINELY AND WHEN WORKING THE AMPLITUDE OFTHE ADVANCE MOVEMENT OF A BAND OF CARDBOARD IN A SHAPING MACHINE FiledJuly 29, 1939 NEE H5566! |NVENTOR= HENRI 0551" ZVZwZV ATTORNEYS press Iand the knife 6.

Patented Nov. 18, 1941 DEVICE FOR CORRECTING FINELY AND WHEN WORKING THEAMPLITUDE OF THE ADVANCE MOVEMENT OF A BAND OF CARDBOARD IN A SHAPINGMACHINE Henri Bobst, Prilly-Lausanne, Switzerland Application July 29,1939, Serial No. 287,330 In Switzerland August 5, 1938 7 Claims.

My invention relates to a device for finely correcting and particularlyduring operation the amplitude of the advance movement of a band ofcardboard in a shaping machine, in which said movement is controlled bya toothed sector, oscillating at an angle of oscillation that can beadjusted.

This fine correction which is effected when working of the amplitude ofthe advance movement of this band of cardboard is obtained according tothe invention, by means making it possible to displace the axle ofoscillation of the toothed sector.

The drawing shows two embodiments of the invention, given by way ofexample; Fig. 1 relates to the first embodiment which is shownsemi-diagrammatically; Fig. 2 shows part of Fig. 1 to which has beenadapted the device according to the second embodiment.

In Fig. 1 the contour in dot and dash line which is designated by thereference numeral I, represents a press for shaping cardboard which isbrought in the form of band 2 in the direction of the arrow 3, under theimpulse communicated to it by two cylinders 4 and 5 between which saidband passes. On coming out of the press I, the band of cardboard can becut by a knife 6, either immediately, or after having been subjectedagain to a certain number of operations under the action of tools whichcould be placed between the The cylinders 4 and 5 cause the band 2 toadvance intermittently and during the pauses, the knife 6 operates.

This intermittent advance is obtained by a mechanism consisting of acrank l which rotates uniformly in the direction of the arrow 8 round anaxle 9 and which moves a sliding member ID in the groove II of the armof a lever which is integral with a toothed sector I2 which, therebyexecutes an oscillating movement. This oscillating movement communicatesa rotative to and fro movement to a toothed pinion [3, which transmitsmotion to the cylinder 5, by means of a free wheel device l4 which actsin such a direction that motion is only transmitted to the cylinder 5when its direction of rotation corresponds to the conveyance of the band2 in the direction of the arrow 3, as it is not set in motion in theother direction.

By moving the crank l by means of the threaded rod l5, so as to draw itnear or away from the axle 9, it is possible to modify the amplitude ofthe oscillating movement communicated to the sector I 2 and thus todetermine the length of the band 2 which is moved at each oscillation.

It is thus possible to shape pieces of cardboard of given lengthcorresponding to the work it is desired to execute.

As the cylinder 5 and the cylinder 4 have a certain mass, their inertiamakes it necessary at the end of the oscillation to brake them if it isdesired that they should stop substantially instantaneously and notcontinue, under the ac.- tion of the impulse received to discharge morecardboard than the amount fixed. For this reason, these two cylindersare braked by means which are shown diagrammatically by the sectors I6,the levers l7 and the spring l8. Generally a mechanism is provided whichhas the effect of releasing the braking means during the period when theband is advancing and of applying them as soon as the sector l2 reachesthe end of its course and reverses its movement.

The mechanism described up to this point is known and operates ondifferent machines for shaping cardboard in band. It has in particularthe following drawback which this invention has the object ofeliminating.

The amplitude of the advance movement which is communicatedintermittently to the band 2 does not remain invariable during worklasting a certain time for, owing either to the overheating of thejournal boxes of the cylinders 4 and 5 and of the wear of the machine ingeneral, or to an irregularity in the nature of the material to beworked, or to an overheating of the braking members-of the cylinders 4and 5 slight variations occur in the advance. The machine must then bestopped in order to shift the shaping members or to rectify the positionof the crank 1 in the direction of the correction desired.

A variation is likewise noticed in the amplitude of the advance movementvarying according to the speed of the machine, and this is easilyaccounted for in view of the inertia of the mechanical pieces inmovement, in particular of the cylinders 4 and 5 which the brakingmembers will not be able to stop so suddenly if they are started at highspeed as if they rotate slowly. Consequently, when the machine isadjusted by making it rotate slowly, it is found that once the normalworking speed has been re-established, the machine is out of order.

This disorder resulting therefrom can be fairly important and it is notunusual with pieces of cardboard discharged 30 inches in length toobtain 30.1 inches when passing from the slow regulating speed to thefast working speed. As this slight error of 0.1 inch is multiplied bythe number of pieces in work between the press and. the knife 6, it willbe seen that this error constitutes fairly important drawback, inparticular if the knife 6 is at a certain distance from the pivot I9makes it possible to cornmunicate to the oscillation axle of the toothedsector can be very small with respect to the displacement communie catedto said pivot, it is thus possible to obtain an extremely fineadjustment. 'It is clear that, owing to said adjustment, the engagementof the sector I2 with the pinion I3 will be a little'modified, but yetto an extent which is not liable to interfere with the good working ofthe machine.

For the correction to be effective, the oscillation axle of, the toothedsector must move, in particular in a direction which is as near aspossible to that of a line joining the oscillating centre of the sectorto the centre of the axle 9, and for the modificationin the engagementof the sector I2 with the pinion I3 to be as little as possible it isnecessary to move the sector as little as possible in the direction of aline joining the oscillation centre of said sector to the axle of saidpinion. In the embodiment according to Fig. 1, the arrangement adoptedwhich, substantially, gives the best results-is such that the pivot I9is capable of being moved on either side of a middle position in whichthe rotation axle of. the toothed sector, that of the toothed pinionwith which it engages and the eccentric axle round which the pivot canrotate, are in line in a common plane.

' The displacement of the pivot I9 can be effected by hand, by means ofa lever 2|, with which it is integral, of a system of rods 22 and of acontrol hand-wheel 23 acting on a threaded part 24 of this system ofrods. The gearing down obtained by this arrangement makes it possible toproceed to a still finer adjustment. As the hand wheel 23 is axiallyretained by the abutments 25, it will clearlybe seen how ;the rotationof the wheel will impart to the system of rods 22 an axial movement ofdisplacement,

making the lever 2| rotate simultaneously with the pivot I9 which isintended to cause the displacement of the oscillation axle of thetoothed sector. t

In the example shown, this simple arrangement has been completed with alever 26 which is capable of oscillating round an axle 21 and of movingthe abutments 25 by the action ofan eccentric 28, said abutments beingcarried by a support sliding in the guides 29 in a direction parallel tothe system of rods 22. It will be seen that by causingthe lever 26 topass from theposition in full line to the position 26 in dot and dashline, a displacement is effected of the abutments 25, of the wheel 23,of the system of rods 22, of the lever 2|, of the pivot I9 and, thereby,of the oscillation axle of the toothed'sector. The amplitude of thisdisplacement can be adjusted exactly by modifying the position of theabutment screws 30.. I a 1 The utility of this perfecting of the devicedescribed consists in the fact that the whole can :ing speed ofthemachine.

It is of course an important feature herein to control the displacementof the pivot |9 in any practical manner, while the modification inadjustment corresponding to the slow and to the fast rate .of working,that is to say, the action obtained-by the swinging of the lever 26 isalso quite practical when it is desired to include the same.

Fig. 2 shows amodification constituting a secondembodiment of thedev-icejust described. In

this figure can be recognized thesector I2, shift-,

ing in position by virtue of its pivot I9 rotating or rotation oftheeccentric shaft 20 caused by the modifications in angular position thata system of rods 22 can impart during operation to the lever 2|. Butzinthis figure this lever is in two pieces 2| and-3|. One end of the part2| is integral with the pivot I9, the other end isarticulated at 32 atone of the ends of the part 3|, the free end of which is operated:at-,33by the system of rods 22;. An extension 34-of this part 3| can oscillatebetween two adjustable abut ments 35, .36. It is clear that even if,while maintaining the system of rods 22 motionless, the position of thepart 3| of the lever isv modified within the limits allowed by theabutments 35,- 36, the part 2| of thislever is oscillated and, thereby,the position of the pivot. I9 is modified and consequently, theoscillation axle of the toothed sector is moved between given limits;This arrangement can for instance replace the lever 26 of the previousexample, and be used to pass instantaneously fromtheadjustment at theslow rate tothe adjustment at the fast rateof working. In the exampleshown, this operation is effectedelectrically by means .of an electro:magnet 31, which is connectedto the part- 2| of thelever and which'actsby, means of the rod 38 against the actionof a spring 39 on an arm 40 ofthe part 3| of the lever.-

. The excitation of said electro-magnet can be effected as indicatedabove under the action. of any organ of the machine with which thedevice co-operates. Y

What I claim is: m 1. In a devicefor fine correction during operation ofthe amplitude of intermittent feeding movement of a band of cardboardthrough-a,

shaping or pressing machine having a pair of rollers forfeeding thecardboard, a pinion connected by means of a one-way clutch to one-ofsaid rollers, and a gear sector rockably mounted on the machine inpermanentmesh with said pinion, with drive means for rocking oroscillating said gear sector, the combination of a shaft supporting andforming a pivotal mounting for said gear sector, said gear sector beingoscillatable upon the pivotal mounting, andmeans for shifting said shafteccentrically in order to vary the degree of oscillation of said gearsector, by altering the relative position of the; latter with respect tothe drive meanstherefor.

2. In a device for fine correction during operation of the amplitude ofintermittent feeding movement of a band of cardboard through a shapingor pressing machine having a pair of rollers for feeding the cardboard,a pinion connected by means of a one-way clutch to one of said rollers,and a gear sector rockably mounted on the machine in permanent mesh withsaid pinion, with drive means for rocking or oscillating said gearsector, the combination of an eccentric forming the pivotal mounting ofand supporting said gear sector, and a shifting arm rigid with saideccentric for partly rotating the same in order to vary the degree ofoscillation of said gear sector, and alter its relative position withrespect to the drive means therefor.

3. A device according to claim 2, wherein the eccentric axis and theaxis upon which the eccentric rotates and that of the pinion with whichthe gear sector meshes are disposed in a single plane in the middleposition of the eccentric and said gear sector.

4. A device according to claim 2, wherein manual means are included forfine adjustment of the shifting arm in order to manually produceextixnfily fine adjustments of the eccentric about its axis.

5. A device according to claim 2, wherein a link member is connected tothe outer end of the shifting arm, and a rotatable member is screwedupon a thread on said link member and abutment means are included fordetermining an axially fixed position of said rotatable member so thatrotation thereof will cause axial movement of the link member withconsequent shifting of the shifting arm and partial rotation of theeccentric.-

6. A device according to claim 2, wherein a link member is connected toone end of the shifting arm, means are connected to said link memberhaving a pair of abutment means and an eccentric is disposed betweensaid abutment means having a lever for partly rotating said eccentric inorder to shift the abutment means and the link member and thereby adjustthe angular position of the shifting arm.

7. A device according to claim 2, wherein a link member is connected toone end of the shifting arm, means are connected to said link memberhaving a pair of abutment means and an eccentric is disposed betweensaid abutment means having a lever for partly rotating said eccentric inorder to shift the abutment means and the link member and thereby adjustthe angular position of the shifting arm and wherein adjustable stopsare located in spaced positions in the path of said lever so as to allowshifting of the shifting arm through the link member from onepredetermined position to another predetermined position and therebydetermine two different adjusted positions of the eccentric.

. HENRI BOBST.

